Transaction Throughput vs Threads

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Don't forget to set up saving thread counts when running in non-GUI mode!

This listenter is very similar to Response Times vs Threads, exept it shows total server's transaction throughput for active test threads. The formula for total server transaction throughput is <active threads> * 1 second / <1 thread response time>.

Example calculations:

  • when you have one thread (user) sending requests to server and server responds after 100ms, you have 1 thread * 1000ms / 100ms = 10 transactions per second.
  • when you have 10 threads sending requests to server and server responds after 100ms, you have 10 threads * 1000ms / 100ms = 100 transactions per second. This means that your server haven't reached its resources limits and the more users works with it the more transaction it processes.
  • when you have 20 threads sending requests to server and server responds after 200ms, you have 20 threads * 1000ms / 200ms = 50 transactions per second. This means that at 20 parallel users server become responding slower and there's some overhead to handle parallelism, e.g. database locks.

So basically, it shows the statistical maximum possible number of transactions based on number of users accessing the application. In the bellow graph, we can see for the transaction named 'First Access':

  • If one user alone access the application, he will have a maximum of 2 transactions per seconds
  • If two users access the application, both will have a maximum of 4 transactions per seconds
  • etc.